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Published in final edited form as: Ultrasound Med Biol. 2013 Sep 21;39(12):10.1016/j.ultrasmedbio.2013.08.004. doi: 10.1016/j.ultrasmedbio.2013.08.004
© 2013 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved